My friend does plexiglass forming.  Wooden frame, kitchen oven element 
for heater.  Large air-tanks connected to a pump.  These are pumped out, 
then a valve opens and the vacuum forming happens very quickly. 
David

Roland wrote:

>>BTW, the hard parts of vacuum forming seem to be the matter of an oven big
>>enough for the work and creating a vacuum source (or is it sink?) with
>>enough volume to draw down the material before the material cools out of the
>>plastic condition...
>>    
>>
>
>Hi 
>
>I've watched vacuum forming done, and it was a very simple set-up. They
>were forming polystyrene(not foam!)
>The positive/pattern was simple wood fabrications, and there was no oven,
>rather a big element and a few fans blowing the air down. I think the
>vacuum part was just an industrial blower, as a sucker.
>
>The force required will depend on the temperature, depth of draw required,
>thickness of sheet, resolution of pattern. Although a nice convoluted
>surface can be obtained, the edges always pose a problem, same with
>fibreglass moulds. Trimming them to an exact size, and polishing to hide
>the work, is almost impossible.
>
>
>  
>
>>A home vacuum cleaner arrangement is not really up to the task. Besides, my
>>earlier experiments with home vacuums lead me to believe a lot of air FLOW
>>is essential to avoid toasting the motors.
>>    
>>
>
>maybe a powerful blower and a venturi will be better??
>
>Regards
>Roland Jollivet
>
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>  
>



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